last week I decided to buy an astroscan for sentimental reasons, I always wanted to have one but never bought one. It came quite dusty and the optics was pretty dirty. Last weekend I managed to disassemble the optics and cleaned the primary (some fungus on it), renewed the foam pad and center marked it and cleaned the glass plate. Then I reassembled it and did some collimation work. I got it collimated ok, but not perfectly collimated.
I still have to work on the focusser, which seems to loose contact beween the tube and the focusser bearing.
It came with the 28mm RKE eyepiece. I gave the scope a try and so far I like it's low power views of the milky way and some Messier objects like M45.
I would also like to contribute a serial number and some details of my astroscan:
Serial number: 26591, blue sticker
Serial number of the primary: 91481, green sticker on it, 4 1/4" f/4, see picture
Label on the glass plate says: Edmund Scientific CO, Astroscan, Pat. No. 0247.004, Barrington N.J.
Sun warning label (bleached out) on top of the focuser
My question is now if this astroscan is made in US or made in Japan?
Something surprised me when I disassembled the optics. On the back of the primary there was a serial number (as given above) and the diameter and focal ratio mentioned: 4 1/4" f/4
If I calculate correctly this yields 108mm diameter and a focal length of 432mm. So far I have only seen 105mm diameter and focal length 445mm, which results in f/4.23. I don't know why the primary specifications are given differently than written by the manufacturer?
Edited by Drainpipeviewer, 28 October 2020 - 03:55 PM.